Light-emitting element and light-emitting device

Abstract

A light-emitting element includes a light absorption layer for transmitting at least part of light that is visible light of a first color emitted by a light-emitting layer in a functional layer and absorbing at least part of visible light other than the light. The light absorption layer is disposed adjacent to both a reflective layer and a first electrode and covers the entire reflective layer in a light-emitting region.

1 . A light-emitting element comprising:
 a reflective layer;   a light absorption layer;   a first electrode that is transparent to visible light;   a functional layer including at least a light-emitting layer configured to emit visible light of a first color; and   a second electrode that is transparent to visible light, all of which are provided in a stated order, wherein   the light absorption layer
 transmits at least part of the visible light of the first color and absorbs at least part of visible light other than the visible light of the first color, 
 is disposed adjacent to both the reflective layer and the first electrode, and 
   covers the entire reflective layer in a light-emitting region of the light-emitting element.   
     
     
         2 . The light-emitting element according to  claim 1 , wherein the visible light of the first color has a light-emission spectrum with a full width at half maximum of less than or equal to 50 nm. 
     
     
         3 . The light-emitting element according to  claim 1 , further comprising an edge cover on the first electrode opposite the light absorption layer, the edge cover covering an edge of the first electrode, wherein
 the edge cover is absorptive to visible light, and   the edge cover directly or indirectly covers a portion of the reflective layer that is out of the light-emitting region.   
     
     
         4 . The light-emitting element according to  claim 1 , further comprising a low-refractive-index layer adjacent to a face of the second electrode opposite the functional layer, the low-refractive-index layer having a lower refractive index than an average refractive index of layers from the first electrode through the second electrode in the light-emitting region, wherein
 the average refractive index of the layers from the first electrode through the second electrode in the light-emitting region differs from the refractive index of the low-refractive-index layer by a larger refractive index difference than the average refractive index of the layers from the first electrode through the second electrode in the light-emitting region differs from a refractive index of the light absorption layer.   
     
     
         5 . The light-emitting element according to  claim 4 , wherein the low-refractive-index layer is made of a resin having a refractive index of from 1.3 to 1.6, both inclusive. 
     
     
         6 . The light-emitting element according to  claim 4 , wherein the low-refractive-index layer is made of a hollow-bead-containing resin containing a plurality of hollow beads. 
     
     
         7 . The light-emitting element according to  claim 4 , wherein the low-refractive-index layer is either hollow or a gas layer. 
     
     
         8 . The light-emitting element according to  claim 4 , further comprising a circular polarizer plate on the second electrode opposite the functional layer with the low-refractive-index layer being interposed between the circular polarizer plate and the second electrode. 
     
     
         9 . The light-emitting element according to  claim 1 , wherein the reflective layer has at least one depression with an inclined inner wall face in the light-emitting region. 
     
     
         10 . The light-emitting element according to  claim 9 , wherein the light absorption layer is thicker in a portion of the light absorption layer that covers the depression in the reflective layer in the light-emitting region than in a portion of the light absorption layer that covers a part of the reflective layer other than the depression in the light-emitting region. 
     
     
         11 . The light-emitting element according to  claim 9 , further comprising a first insulating layer on the reflective layer opposite the light absorption layer, the first insulating layer having at least one depression with an inclined inner wall face in the light-emitting region, wherein
 the reflective layer is disposed along at least a part of a surface of the first insulating layer at least in the light-emitting region so as to cover at least a part of the inner wall face of the depression in the first insulating layer.   
     
     
         12 . The light-emitting element according to  claim 11 , wherein
 the first insulating layer includes a plurality of the depressions in the light-emitting region, and   the reflective layer covers at least the entire inner wall faces of the plurality of the depressions in the first insulating layer in the light-emitting region.   
     
     
         13 . The light-emitting element according to  claim 11 , wherein the reflective layer covers a part of the inner wall face of the depression in the first insulating layer in the light-emitting region. 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . (canceled) 
     
     
         17 . (canceled) 
     
     
         18 . The light-emitting element according to  claim 11 , wherein the first insulating layer is absorptive to visible light. 
     
     
         19 . The light-emitting element according to  claim 11 , wherein the depression in the first insulating layer has at least a linearly formed portion. 
     
     
         20 . The light-emitting element according to  claim 1 , wherein the light absorption layer has a higher transmittance to light of a maximum light-emission luminance wavelength of the visible light of the first color than to the at least part of visible light other than the visible light of the first color. 
     
     
         21 . The light-emitting element according to  claim 1 , wherein the light-emitting layer contains quantum dots configured to emit the visible light of the first color. 
     
     
         22 . A light-emitting device comprising a plurality of the light-emitting elements according to  claim 1 . 
     
     
         23 . The light-emitting device according to  claim 22 , wherein
 the plurality of the light-emitting elements include a red light-emitting element configured to emit red light as the visible light of the first color, a green light-emitting element configured to emit green light as the visible light of the first color, and a blue light-emitting element configured to emit blue light as the visible light of the first color, and   the light absorption layer in the red light-emitting element and the light absorption layer in the blue light-emitting element have a higher transmittance to light of a maximum light-emission luminance wavelength of the red light and to light of a maximum light-emission luminance wavelength of the blue light than to visible light other than the red light and the blue light.   
     
     
         24 . The light-emitting device according to  claim 22 , wherein
 the plurality of the light-emitting elements include a red light-emitting element configured to emit red light as the visible light of the first color, a green light-emitting element configured to emit green light as the visible light of the first color, and a blue light-emitting element configured to emit blue light as the visible light of the first color,   the light absorption layer in the red light-emitting element has a higher transmittance to light of a maximum light-emission luminance wavelength of the red light than to visible light other than the red light,   the light absorption layer in the green light-emitting element has a higher transmittance to light of a maximum light-emission luminance wavelength of the green light than to visible light other than the green light, and   the light absorption layer in the blue light-emitting element has a higher transmittance to light of a maximum light-emission luminance wavelength of the blue light than to visible light other than the blue light.